Sea level rise has worsened high tide flooding in Venice, submerging wide areas of the city such as the iconic Piazza San Marco, seen here in 2008. Andrea Pattaro/AFP/Getty Images

Rising Waters: Can a Massive Barrier Save Venice from Drowning?

A retractable barrier designed to protect Venice from sea level rise and storm surges is set to be operational next year. But the project’s engineering limitations and cost overruns are raising questions about the mega-projects that many coastal cities are hoping can save them.

By Jeff Goodell